Casey Downey died in 2010.

Casey Downey's body was found Feb. 7, 2010, by RCMP officers responding to a weapons call in North Preston. (CBC)

A 28-year-old Halifax man must wait until January to learn whether he'll be convicted of second-degree murder in the death of a teenager more than three years ago.

Demarco Smith was charged after a stabbing at a house party in North Preston in February 2010. Casey Downey, 19, died from a single stab wound to the chest.

Smith's murder trial wrapped up Monday in the Supreme Court of Nova Scotia. He's claiming self defence and testified that Downey lunged at him and essentially impaled himself on the knife Smith was holding.

"We're submitting to the court that it's not believable," Crown attorney Roland Levesque said after closing arguments.

Pam Downey, Casey Downey's mother, was in court for Smith's two-week trial.

"It's been hell on earth, really," she said. "Every day, I cry every day, because I've lost my son."

Argument over DJ's speakers

The court was told Downey was stabbed after he and Smith argued at the end of the evening. Downey was insisting Smith help the DJ carry out his equipment.

"A minor, stupid argument," Levesque said. "[Over] carrying out speakers."

"That makes me think that people are really stupid," Pam Downey told reporters outside court. "They just go around killing people for nothing."

Smith's lawyer is arguing his client acted in self defence and should be found not guilty. Failing that, the defence is arguing the killing was unintentional and Smith should be found guilty of manslaughter.  

The Crown wants Smith convicted of second-degree murder, which carries a mandatory sentence of life in prison.

The victim's mother hopes for a heavy sentence if Smith is convicted.

"I hope he gets a lot of time, a whole lot of time," Pam Downey said. "Set an example for a lot of these people down there, young boys and girls, that's going out taking other people's lives. I hope he gets a lot of time."

Justice Patrick Duncan will hand down his ruling on Jan. 8.